lemma vs flowering glume

lemma and flowering glume both are nouns.

Word	Noun	Adjective	Verb	Adverb
lemma	Yes	No	No	No
flowering glume	Yes	No	No	No

As nouns, lemma and flowering glume are synonyms defined as:

lemma and flowering glume: the lower and stouter of the two glumes immediately enclosing the floret in most Gramineae

lemma (noun)	flowering glume (noun)
a subsidiary proposition that is assumed to be true in order to prove another proposition	the lower and stouter of the two glumes immediately enclosing the floret in most Gramineae
the heading that indicates the subject of an annotation or a literary composition or a dictionary entry
the lower and stouter of the two glumes immediately enclosing the floret in most Gramineae